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Ye Huawen Christian K?nig Thomas Ummenhofer Qiang Shizhong Robin Plum 《Canadian Metallurgical Quarterly》2010,14(5):609-615
An experimental and analytical study was conducted to investigate the fatigue behavior of tension steel plates strengthened with prestressed carbon-fiber-reinforced polymer (CFRP) laminates. A simple fracture mechanics model was proposed to predict the fatigue life of reinforced specimens. Double-edge-notched specimens were precracked by fatigue loading and then strengthened by CFRP laminates at different prestressing levels. The effects of the applied stress range, CFRP stiffness, and prestressing level on the crack growth were investigated. Experimental results show that the increase of the prestressing level extends the fatigue life of a damaged steel plate to a large amount. The CFRP with the highest prestressing level performed best, prolonging fatigue life by as much as four times under 25% higher fatigue loading. Theoretically, predicted results were in a reasonable agreement with the experimental results. A parametric analysis was also performed to investigate the effects of the applied stress range and the prestressing level on the debonding behavior of the adhesive and on the secondary crack propagation. 相似文献
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Contextual conditioning during relative validity training was explored in 3 experiments that used an appetitive Pavlovian conditioning preparation with rats. Magazine entries were the conditioned response. In Experiment 1, true-discrimination (TD: AX+, BX–) training generated weaker conditioning of X than did pseudodiscrimination (PD: AX+/–, BX+/–) training. The context showed a similar relative validity effect. Also, both PD training and simple partial reinforcement (X+/–) reduced contextual conditioning more than did unsignaled food, a demonstration of relative validity using partial reinforcement. Experiments 2 and 3 used within-subject and between-subjects designs, respectively, and showed that relative validity was determined by the summation of differences in conditioning to both the common element (X) and the context. The results are consistent with an attentional model or with a computational comparator model but not with the Rescorla-Wagner (R. A. Rescorla & A. R. Wagner, 1972) model. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Kochanska Grazyna; Barry Robin A.; Jimenez Natasha B.; Hollatz Amanda L.; Woodard Jarilyn 《Canadian Metallurgical Quarterly》2009,97(2):322
Children’s guilt associated with transgressions and their capacity for effortful control are both powerful forces that inhibit disruptive conduct. The authors examined how guilt and effortful control, repeatedly observed from toddlerhood to preschool age, jointly predicted children’s disruptive outcomes in 2 multimethod, multitrait longitudinal studies (Ns = 57 and 99). Disruptive outcomes were rated by mothers at 73 months (Study 1) and mothers, fathers, and teachers at 52 and 67 months (Study 2). In both studies, guilt moderated effects of effortful control: For highly guilt-prone children, variations in effortful control were unrelated to future disruptive outcomes, but for children who were less guilt prone, effortful control predicted such outcomes. Guilt may inhibit transgressions through an automatic response due to negative arousal triggered by memories of past wrongdoing, regardless of child capacity for deliberate inhibition. Effortful control that engages a deliberate restraint may offset risk for disruptive conduct conferred by low guilt. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Haskard Kelly B.; Williams Summer L.; DiMatteo M. Robin; Rosenthal Robert; White Maysel Kemp; Goldstein Michael G. 《Canadian Metallurgical Quarterly》2009,28(2):263
Reports an error in "Physician and patient communication training in primary care: Effects on participation and satisfaction" by Kelly B. Haskard, Summer L. Williams, M. Robin DiMatteo, Robert Rosenthal, Maysel Kemp White and Michael G. Goldstein (Health Psychology, 2008[Sep], Vol 27[5], 513-522). There was a typographical error in the text on page 521, in the first sentence of the first full paragraph. The corrected sentence is provided in the erratum. (The following abstract of the original article appeared in record 2008-13168-002.) Objective: To assess the effects of a communication skills training program for physicians and patients. Design: A randomized experiment to improve physician communication skills was assessed 1 and 6 months after a training intervention; patient training to be active participants was assessed after 1 month. Across three primary medical care settings, 156 physicians treating 2,196 patients were randomly assigned to control group or one of three conditions (physician, patient, or both trained). Main Outcome Measures: Patient satisfaction and perceptions of choice, decision-making, information, and lifestyle counseling; physicians' satisfaction and stress; and global ratings of the communication process. Results: The following significant (p 相似文献
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